1. Field of the Invention
This invention relates to cameras having a battery check device.
2. Related Background Art
It has been conventionally known that there are cameras which detect the power supply voltage (the voltage of power supply batteries) each time half-push operation is performed on a release button, determine and alarm that photographing is disabled when the power supply voltage is lower than a predetermined value. They enable photographers to know the time for replacement of batteries, but there is inconvenience to photographers in the case that they have no new battery where no measure can be taken because photographing has already been disabled when the alarm is given.
It is known that there are cameras which have two-step battery check function wherein a preliminary alarm is given before the cameras become disabled and an alarm is given when photographing has been disabled. With this function, it is possible to know that little battery capacity is left and to take measures such as preparing new batteries. Also, it is known that there are cameras such as those disclosed by U.S. Pat. No. 4,716,433 which count the number of times photographing is performed, calculate and display in stages the remainder of battery capacity on the basis of the count. With this function, it is possible to know the remainder of the battery capacity any time, and when little battery capacity is left, measures such as preparing new batteries as described above can be taken.
However, what photographers really want to know is how many photographs can be taken with the remainder of the battery capacity while the preliminary alarm and the display of the remainder of the battery capacity as described above can only provide a rough idea on such and it is not possible to know specifically how many photographs can be taken, and thus what is really demanded by photographers has not been satisfied.